2017

6.5

1992

5.0

1991

6.1

1990

6.0

1996

5.4

1997

6.9

1977

7.0

1985

6.9

1979

6.7

1994

6.7

2014

5.2

1993

6.0

2009

6.7

2005

5.8

2003

6.8

2009

5.9

1993

6.2

2019

9.1

2014

6.8

1991

6.1